AppleTV/AirPlay/streaming--no picture but there is sound

I tried streaming the ball game from my mobile device (using ATT app) to Apple TV using AirPlay and only get sound. It has always worked for me in the past up until last night. It seems as if it may be playing through the iTunes Radio? I do not know what I did wrong this time around for it to not work like it always has? I tried restarting Appletv, updated the software, checked hdmi connections, but still nothing. Wifi is working as well. I can see the apps on the Apple TV But only get sound when streaming. Frustrating! So if anyone can help it'd be greatly appreciated!